Fuel cells are used to provide an efficient energy supply with a high efficiency. However, the fuel cells in use today have a relatively low availability which is far below the availability of other energy-producing plants, for example, condensation power plants or wind power plants. Furthermore, the fuel cells in use today have relatively poor dynamics, in particular at a high load and/or in the event of a short circuit. Therefore, a complex protective technology must be used for fuel cells. Fuel cells must usually be dimensioned larger to be able to ensure a short-term overload power supply, and therefore they will have a greater weight and a comparatively low power density at the same maximum power level. In addition, the fuel cell membrane cannot be shut down quickly enough when there is a persistently high current load that could damage the fuel cell membrane.
Various types of fuel cells are known from the prior art, for example, alkaline fuel cells (AFC), polymer electrolyte membrane fuel cells (PEFC) or phosphoric acid fuel cells (PAFC) for the low-temperature range and/or melt carbonate fuel cells (MCFC) or solid oxide ceramic fuel cells (SOFC) for the high-temperature range. Such fuel cells are described, for example, in K. Heuck, K. D. Dettmann, D. Schulz: Elektrische Energieversorgung [Electrical Power Supply], 8th edition, Wiesbaden, Vieweg, 2010, page 22. In addition, DE 11 2007 000 666 T5 describes a device and method for monitoring the internal condition of a fuel cell, in which measured values are recorded by sensors for measuring electrode currents, for example. Furthermore, U.S. Pat. No. 6,949,920 B2 describes an apparatus for measuring the current density of fuel cells, in which measured values are picked up on the electrodes of the fuel cells.